Dataset class checks if a field is null by passing a nil buffer. Tell it is null by passing back a result of False. Here is an example. function TMyDataset.GetFieldData(Field: TField; Buffer: Pointer): Boolean; var RecBuffer: PChar; ... begin Result := false; if not FisOpen then exit; //Check datase...

Hi Narcís,

The AddXY method is append, not insert.
I would like to InsertXY( Insert_position_index, X, Y, X_label, Color ).
Is it possible?

When ChartEditor's TreeView property is true, the ChartEditor makes an access vioration run time error under the follow operation: 1. Execute ChartEditor 2. Add LineSeries 3. Expand sub tree of Series node 4. Click 'Chart' tree node 5. Click 'Series' tree node 6. Click 'Chart' tree node 7. Click 'Se...

Hi,

How could I insert data to a ChartSeries and then redraw it?
I would like to X, Y data, its color, and X-label to a line series.

Thanks in advance.

Seungho Jung

Hi, I have solved the my question no. 2 by myself. The TDBChart checks the data nullity by using the TField.IsNull method. I have modified the my own DataSet class to respond correctly to the TField.IsNull method. And about question no. 1, I think that the DBChart uses its own memory buffer for the ...

I have two questions about TDBChart. 1. Does the DBChart series have and use its own memory buffer? I have several large my own dataset of which data is in memory. Therefore if the DBChart series has and uses its own memory buffer, two memory buffer are allocated for the same data, one is for DBChar...

How colud I limit the datasource type, that is, dropdown list items of a ChartEditorPanel at runtime?

My program use only several datasets as the series datasource, so other series datasource types are not necessary and must be invisible.

Thanks in advance.

Seugnho Jung

In Delphi7 application, when insert a QRChart 7.06 on a form or a QuickRep and add a serie to this chart then the QRChart flickers repeatedly.
I think it is a bug.
Could anyone help me?